(1) Field of the Invention
The invention relates to 3-D modeling, in particular, to alignment and/or stitching of various 3-D fragments.
(2) Related Art
In creating a three-dimensional (3-D) model of a real object, a multitude of images of the real object may be taken from different positions to exploit the differences in the object""s projection. Multitude of images may be captured, for example, using an imaging device such as a camcorder or a digital camera comprising an image sensor. The image sensor generally comprises a photo-sensitive pixel array where each pixel captures an incident light falling on it. Thus, the combination of the pixels within the pixel array may be able to capture an image from the incident light. Generally, to re-construct a surface of an object into 3-D model, the surface should be present in at least two images since reconstruction is based on the surface intersection of the two images. These two or more images (i.e. stereoscopic image) of the object having the above characteristics may be suitable for subsequent processing into 3-D models.
With the stereoscopic image in mind for 3-D data extraction, complete objects may not be captured in a single take and perhaps, only a fragment may be captured. The limitation may be perhaps due to the size of the object or the object""s surface contour deviation from a plane which may not be visible by more than one imaging device. In another instance, the object being captured may have occluded surfaces complicating a single take stereoscopic image. An example of an occluded surface may be a full human body with the occlusions being the arms, legs, ears, and etc. Using a mechanical displacement of either the object, the imaging devices or both, various fragments of the object may be captured. Like a jigsaw puzzle, the various fragments may have to be fitted together in its correct position to produce a more complete 3-D model of the object. Generally, the fitting process may comprise an xe2x80x9calignmentxe2x80x9d process and/or a xe2x80x9cstitchingxe2x80x9d process. The alignment process is generally a correct positioning of two or more fragments. The stitching process is generally an interweaving of two or more correctly positioned fragments into one fragment or surface representing the desired 3-D model of the object.
The present invention pertains to a method and apparatus for producing a more complete 3-D model of an object by capturing various fragments of the object, aligning the fragments, and/or stitching the fragments into one surface which may be the 3-D model of the object.
A method and apparatus pertains to aligning and/or stitching together several 3-D fragments. The steps comprise locating at least two fragments having a corresponding set of alignment marks and aligning at least two fragments with respect to a coordinate system using the corresponding set of alignment marks in the respective fragments.